c++ - VS 2017错误C2664 map 插入尝试

Question

class   Thread
    {
    Sync::TYPE  sync;       // synchronous start/finish
    char        name[256];  // thread name
    thread      handle;     // thread handle
    HANDLE      abort,      // abort event handle
            start;      // start event handle

    public:
    Thread(const char *desc,Sync::TYPE ctrl,void (*fn)(void *),void *arg=NULL);
    Thread(Thread &th);
    Thread(void);
    ~Thread(void);
    HANDLE      AbortHandle(void) const     { return(abort); }
    HANDLE      StartHandle(void) const     { return(start); }
    thread::id  ID(void) const          { return(handle.get_id()); }
    void        Name(const char *value);
    const   char    *Name(void) const       { return(name); }
    void        Sync(Sync::TYPE value)      { sync=value; }
    Sync::TYPE  Sync(void) const        { return(sync); }
    thread      *ThreadHandle(void)     { return(&handle); }
    Thread      &operator=(Thread &th);
    };

class   ThreadList
    {
    map<thread::id,Thread>  TiL;

    public:
    ThreadList(void);
    ~ThreadList(void);
    HANDLE                  AbortHandle(void);
    void                    Clear(void);
    bool                    Close(thread::id id);
    void                    Close(map<thread::id,Thread>::iterator pos);
    map<thread::id,Thread>::iterator    Create(char *name,Sync::TYPE sync,void (*function)(void*),void *arg=NULL);
    map<thread::id,Thread>::iterator    Find(thread::id id)             { return(TiL.find(id)); }
    int                 Size(void) const                { return(TiL.size()); }
    void                    Start(map<thread::id,Thread>::iterator pos);
    HANDLE                  StartHandle(void);
    };

现在这段代码产生了错误:

map<thread::id,Thread>::iterator    ThreadList::Create(char *name,Sync::TYPE sync,void (*function)(void*),void *arg)
{
pair<map<thread::id,Thread>::iterator,bool> result;
thread::id                  id;
Thread                      th(name,sync,function,arg);

id=th.ThreadHandle()->get_id();
**result=TiL.insert(make_pair(id,th));**
return(result.first);
}

错误的线路以粗体显示。确切的错误信息是这样的:

错误 C2664:“std::_Tree_iterator>> std::_Tree>::insert(std::_Tree_const_iterator>>,const std::pair &)”:无法将参数 1 从“std::pair”转换为'std::pair &&'

我在这里做错了什么？

亲切的问候，瓦迪姆。

P.S.:抱歉，我当时应该澄清一下。还有那些定义:

Thread::Thread(Thread &th)
{
sync=th.sync;
StrCopy(name,sizeof(name),th.name);
abort=th.abort;
start=th.start;
handle=move(th.handle);
}

Thread  &Thread::operator=(Thread &th)
{
sync=th.sync;
StrCopy(name,sizeof(name),th.name);
abort=th.abort;
start=th.start;
handle=move(th.handle);
return(*this);
}

Answer 1

没有 MCVE很难确定，但是看看你的例子，我看到的最明显的事情是 Thread 类中的 thread handle 。我假设这是一个 std::thread如果是这样，std::thread 状态的文档

No two std::thread objects may represent the same thread of execution; std::thread is not CopyConstructible or CopyAssignable, although it is MoveConstructible and MoveAssignable.

要修复它，您必须实现移动运算符以确保您的 Thread 类可以放置到容器中。

然后您将能够 std::move(th) 到 map 容器中或直接使用 map.emplace 构造它

我建议阅读有关何时以及如何实现复制/移动的文章，因为这些事情很容易出错，而且默认值可能已经足够好了。